What Is Constructive Dismissal in Ontario? A Guide for Employers

Constructive dismissal is one of the more expensive mistakes an Ontario employer can make, and it often happens without anyone in the organization realizing it. An employer makes what seems like a reasonable operational change: a reporting structure adjustment, a compensation revision, a new role following a restructure. The employee resigns. Months later, the employer is in court defending a wrongful dismissal claim they believed they had nothing to do with.

In Ontario, a constructive dismissal occurs when an employer makes a unilateral change to a fundamental term of employment, without the employee’s agreement, that is significant enough to signal an intention to no longer be bound by the original contract. The employee need not be formally terminated. If the change makes the employment relationship materially different from what was agreed, the law treats the employer as having effectively dismissed them.

The Legal Test in Ontario

The Supreme Court of Canada set out the modern constructive dismissal framework in Potter v. New Brunswick (Legal Aid Services Commission), 2015 SCC 10. The analysis proceeds in two steps.

The first is whether the employer made a unilateral change to a substantial term of the employment contract. This requires identifying what the original contract actually required, which is why poorly drafted employment agreements, or no agreement at all, create significant exposure. If the contract is silent on whether the employer can reassign duties, reduce pay, or change reporting lines, a court will ask what the parties objectively understood their obligations to be.

The second is whether a reasonable person in the employee’s position would have felt that the essential terms of employment had been substantially changed. The test is objective, not based on the employee’s sensitivity or the employer’s intention. An employer can make a change in good faith, with genuine business rationale, and still be found to have constructively dismissed the employee if the change was objectively fundamental.

Potteralso confirmed a second route to constructive dismissal: a course of conduct by the employer, even without a single identifiable breach, that when viewed cumulatively demonstrates an intention to no longer be bound by the employment contract. This is the “poisoned environment” branch, and it is harder to see coming.

What Triggers Constructive Dismissal in Practice

The most common constructive dismissal triggers Ontario employers encounter are changes to compensation, duties, reporting relationships, and working conditions. Each carries its own risk profile.

A pay reduction is one of the clearest triggers. Ontario courts have found compensation cuts of 10% to 15% sufficient to ground a constructive dismissal claim, depending on context. For a senior employee with a fixed salary and bonus expectations built into the working relationship over time, even a smaller reduction may be enough. The key question is whether compensation was a fundamental term, and for most employees, it is.

A significant demotion, reduced title, loss of direct reports, removal from a key decision-making role, is treated similarly. The employer may frame it as a restructure. What matters legally is how it compares to what the employee was hired to do and what they had been doing.

Changes to reporting structure can also cross the line, particularly where a senior leader is reassigned to report to a peer or junior colleague, or where the scope of their authority is substantially reduced without a corresponding change in title or pay. Courts look at the practical impact on the employee’s role, not just whether the org chart changed.

A poisoned work environment, workplace harassment, targeted humiliation, or systematic exclusion, can ground a constructive dismissal claim even without any formal change to terms. This is the branch of the test that keeps HR compliance practitioners up at night, because the employer may not realize the cumulative effect of management conduct until an employee resigns and a lawyer writes a letter.

The Continuation Problem

One of the most misunderstood aspects of constructive dismissal is what happens after the employer makes the change. Ontario courts have held that an employee who continues to work under the new terms for a significant period, without objection, may be found to have accepted those terms. This is the mirror image of the condonation doctrine in discipline cases, here, the employee who stays too long risks losing the claim.

What this means practically is that the employee typically needs to act promptly: resign and sue, or formally object in writing while reserving the right to treat the change as a constructive dismissal. Continued acceptance without protest weakens the case over time. Most experienced employment lawyers advise clients to document their objection quickly and decide within a reasonable period.

From the employer’s side, this creates a false sense of security. An employer who made a compensation change six months ago, with the employee saying nothing and continuing to show up, may believe the matter is resolved. It may not be. The employee may still have a viable claim depending on the nature of the change and how courts assess the continuation period. The employer should not interpret silence as consent.

Why Employers Get Caught Off Guard

Most constructive dismissal claims do not arise from malicious conduct. They arise from restructures, budget pressures, and operational decisions made without a legal review of the employment contract or the common law obligations that fill in whatever the contract does not say.

The pattern is consistent: an employer acquires a new business, integrates teams, and needs to consolidate roles. Or a founder exits and the new leadership team adjusts compensation structures. Or a company goes through a downturn and reduces salaries across the board. In each case, real business pressure exists, the change seems reasonable, and nobody thinks to ask whether any affected employee has a constructive dismissal argument.

The other common source of exposure is the employment contract itself, or the absence of one. An employer without a current, properly drafted employment agreement for each employee cannot rely on implied flexibility to make significant changes. The common law implied term in Ontario is that employment continues on the same material terms unless the employee agrees otherwise. Employers who have been operating on verbal agreements or outdated offer letters are particularly exposed. An HR retainer that includes regular contract reviews catches this before a change event forces the issue.

What to Do Before Making the Change

Before implementing any significant change to a senior employee’s compensation, duties, title, or reporting structure, an Ontario employer should be working through the following analysis.

The first question is whether the employment contract expressly permits the proposed change. Many contracts include flexibility clauses, provisions authorizing the employer to reassign duties or adjust compensation within a defined range. If a valid flexibility clause covers the change, the employer is in a much stronger position. If the contract is silent, assume the common law default applies and the change requires consent.

The second question is whether the affected employee can be brought along. In many cases, the practical solution is to present the change transparently, explain the business rationale, obtain written agreement to the revised terms, and provide fresh consideration, additional compensation, extended notice entitlements, or another benefit that makes the consent enforceable. An agreed-upon change is not constructive dismissal. A unilateral one may be.

The third question is what the exposure looks like if the employee refuses. For a senior employee with ten to fifteen years of service in a managerial role, a constructive dismissal finding means the employer owes reasonable notice at common law, typically ten to fourteen months, or more in some circumstances. With total compensation of $125,000 per year, that translates to roughly $105,000 to $145,000 in damages before legal costs and management time are factored in. Knowing this number before implementing the change informs whether the business rationale justifies the risk, and whether a without-cause termination package would have been a cleaner exit from the start.

The Practical Bottom Line for Ontario Employers

Constructive dismissal claims in Ontario are not difficult to understand once the framework is clear: the employer made a unilateral change to a material term of employment without the employee’s agreement, and the employee left as a result. The difficulty is that most employers do not recognize the risk at the point of decision-making, they recognize it when the resignation letter arrives.

The straightforward prevention is pre-change analysis. Before restructuring a senior role, revising compensation outside the range the employee agreed to, or making any change that materially alters what the employee shows up to do each day, get the employment contract reviewed against the proposed change. If the contract does not support it, obtain written consent with adequate consideration, or structure a clean without-cause termination. The cost of that review is a small fraction of what a constructive dismissal claim costs once the employee is already out the door.

This article is for general information only and is not legal advice. Consult qualified counsel for advice on specific situations.